812101272234821 has 2 divisors, whose sum is σ = 812101272234822. Its totient is φ = 812101272234820.

The previous prime is 812101272234809. The next prime is 812101272234871. The reversal of 812101272234821 is 128432272101218.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 656349249830596 + 155752022404225 = 25619314^2 + 12480065^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-812101272234821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (812101272234871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406050636117410 + 406050636117411.

It is an arithmetic number, because the mean of its divisors is an integer number (406050636117411).

Almost surely, 2^{812101272234821} is an apocalyptic number.

It is an amenable number.

812101272234821 is a deficient number, since it is larger than the sum of its proper divisors (1).

812101272234821 is an equidigital number, since it uses as much as digits as its factorization.

812101272234821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 172032, while the sum is 44.

The spelling of 812101272234821 in words is "eight hundred twelve trillion, one hundred one billion, two hundred seventy-two million, two hundred thirty-four thousand, eight hundred twenty-one".